The present invention relates to electrical connectors of the type used in manufacturing automation systems. In particular, the invention relates to improvements in a DIN connector for mounting to the body of a solenoid while providing electrical connectors for operating the solenoid. Such connectors are currently widely used. They comply with internationally recognized standards, as persons skilled in the art will readily appreciate.
Prior art devices adapted for establishing the necessary electrical connections in the field (that is, at the site where the connection to a solenoid or other electromechanical actuator is required) have employed reliable but cumbersome techniques for establishing electrical connections. For example, set screws were used in combination with apertured connector blocks. It requires that the wires be stripped (typically there are four incoming wires in a feed cable); and the stripped ends are placed in associated connector blocks and the set screws then tightened. As persons skilled in the art will readily appreciate, connectors of this type are fairly small, and field conditions for establishing connections are not always desirable, resulting in a time-consuming and sometimes difficult conditions under which to establish a connection. Another problem with prior art connectors of this type involves a gasket associated with the connector. The connector, once the connections with the feed cable are made, is assembled by means of a screw to a base mounted to the body of the solenoid. The fixed base mounts the prongs forming the male connector receiving the instant connector, which is a female. A flexible gasket is interposed between the exterior housing the connector and the base on the solenoid. Over time, and particularly in use conditions where the connector is exposed to oils or other corrosive materials, the gasket becomes soiled or damaged, and it is desired to replace the gasket. This is sometimes desired merely in the course of normal maintenance or repair, whether the gasket is damaged or not. Thus, some connector manufacturers provide gaskets which are removable from the housing of the connector. If the gasket is permanently mounted to the housing, it is difficult or time-consuming to replace it, and some customers desire removable gaskets. When the connector comes with a removable gasket, it sometimes becomes deformed during extended use, and during repairs or maintenance it may be dropped or lost.
The present invention solves the problem of establishing the necessary electrical connections in the field by using connection techniques involving displacing the insulation of the wire and establishing the connection without having to strip the end of the wire of its insulating jacket. The particular structure for establishing the insulation displacement connection (IDC) includes the use of a specially shaped contact seated in the contact holder of the connector body and including a laterally extending portion which provides an aperture for receiving the wire and converging, sharp edges for piercing the insulation and contacting the wire to establish the connection. To establish the contact, a pusher member is aligned with the horizontal portion of an associated contact, and the unstripped end of the wire is aligned with a vertical aperture in the pusher member as well as the enlarged portion of the cutting slot in the contact. The pusher member is then pushed onto the contact to move the wire into the cutting portion of the contact aperture, thereby establishing the connection. The pusher member is then secured to the housing by means of a barb, maintaining the established contact. This is repeated for each of the four wires.
The base of the contact holder is provided with a generally rectangular cavity forming a receptacle which is sized to receive a retainer member. The gasket is removably held in place by the retainer member in the form of a pedestal having a central projection which is dimensioned to provide an interference fit into the receptacle formed by the rectangular aperture in the base of the contact holder. This facilitates replacement of the gasket as desired.
Other features and advantages of the present invention will be apparent to persons skilled in the art from the following detailed disclosure of the exemplary embodiment accompanied by the attached drawing wherein identical reference numerals will refer to like parts in the various views.